How Humans Explore Objects via Touch

People rapidly and accurately identify 3-dimensional objects using only their sense of touch [1]. This process occurs through a sequence of exploratory procedures that underlie the cognitive strategies used to conclusively identify an object entirely through its haptic features. The following four procedures are the most common methods for tactile exploration [2].

Lateral Motion
By moving their fingers across a surface, an individual can perceive the texture of an object and its temperature. The uniformity of temperature and texture can help identify the object by indicating its material construction.

Pressure
By applying pressure to an object, its material construction can be further elucidated—soft and hard materials are present in different objects. Further, the elasticity of an object in response to pressure can be detected by the fingers.

Enclosure
Enclosing an object with the hands (or attempting to enclose the object) provides an approximation of its size as well as information about the features of its 3-dimensional shape.

Contour Following
When an object is too large to enclose, people frequently attempt to follow the contours of the object to extrapolate its 3-dimensional shape.

For a virtual reality or augmented reality interface to conform to human intuition, it must provide tactile feedback corresponding to these explorations of the surface of an object.